Fast-food and take-away outlets are being blamed for contributing to an outbreak of salmonella food poisoning across the north of England and the Midlands.
The Government's Health Protection Agency has said that the outbreak has seen 350 cases reported so far, spread across north-east Lincolnshire, Birmingham, the West Midlands, Northern Ireland and the Isle of Man.
Dr Bob Adak, who is leading the investigation for the agency, said: "Investigations into the cause of this outbreak have been carried out both on a local and a national level using questionnaires to establish any common foods eaten in the days before people became ill.
"In some of the local investigations the results suggest that consumption of lettuce from various catering, fast food and take-away premises are the likely main cause of the outbreaks."
Judith Hilton, head of microbiological safety at the Food Standards Agency, reiterated the need for good hygiene in kitchens, particularly in handling salads and lettuce.
"Food Standards Agency advice is that the risk of food poisoning can be reduced by good food hygiene practices.
"These include thorough washing and preparing of lettuce away from other foods to avoid cross-contamination and storing it in the fridge before it is served, because at warmer temperatures salmonella can grow," she said.
by Nic Paton
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